


King of the Empty Spaces

by seperis



Series: The Forever King [4]
Category: Supernatural
Genre: Alternate Universe, Alternate Universe - Canon, Alternate Universe - Canon Divergence, M/M
Language: English
Status: Completed
Published: 2020-12-30
Updated: 2020-12-30
Packaged: 2021-03-10 22:27:43
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 12,019
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28424727
Author URL: https://archiveofourown.org/users/seperis/pseuds/seperis
Summary: This is Hell; a lie holds as much power as the truth.
Relationships: Castiel/Dean Winchester
Series: The Forever King [4]
Series URL: https://archiveofourown.org/series/1233668
Comments: 13
Kudos: 76
Collections: Down to Agincourt Fanworks





	King of the Empty Spaces

**Author's Note:**

  * Inspired by [The Game of God](https://archiveofourown.org/works/4592838) by [seperis](https://archiveofourown.org/users/seperis/pseuds/seperis). 



> Nothing says Christmas like some domesticity, power games, Hellhound breeding programs, and recreational torture in Hell. 
> 
> Set after [All the King's Men](https://archiveofourown.org/works/17224955) and that scene in Book IV, Chapter 10. All my love and appreciation to campchitaqua for walking through it with me on Twitter and helping me find the problems and work out the solutions.

This isn't the first time Dean's had to stop and take a moment when confronted with Cas exercising his creativity in the Pit--it's never not been fucking awesome--but he can honestly state at no time did this form ever cross his mind.

"Is that grass?" his companion asks.

"Looks like it." About ten acres of perfectly mown grass just--sitting there, like a lawn transplanted from suburbia. Illusion, construct, or maybe the real thing (how? Cas): it's not like there's any difference between them here. "I wonder where he's putting the garden?"

She stiffens; while no one's allowed to see work in progress (even Dean, fuck it), everyone's very aware Cas is perfecting Act 6 of his latest installation and is always pleased to get new material for his drafts. Her eyes abruptly narrow; following her gaze, he sees Cas and Vera pacing the perimeter, Fido, Spot, and a pup at their heels.

"I see Castiel's enjoying his new toy."

"When I'm good, I'm good." He watches Cas stop to check something, Vera watching him closely. Generally, plans exist only to disappoint you, but not this time. Once they got past the fuck-up on the rack and the fallout, anyway. Sure, they had to wait longer than they expected, but Vera sure as fuck didn't waste those years. She knows more about the Pit now than most demons ever guess; maybe a few--other than him and Cas, of course--might know more, but he wouldn't bet on it. On a guess, she also probably knows more about Hell itself than anyone but him, Cas, and the oldest demons still in existence, if those very well-concealed excursions beyond the borders are anything to go by.

(He still can't get over it; powerless, practically helpless, and falling half-apart, she wandered in and out of territories even the strongest demons--including his lieutenants--wouldn't risk entering without an army at their back, skimming the borders of unclaimed territories and the no-lands before walking on her own two not-even-fucking-there feet into one of the strongholds of the putative rulers of Hell itself and stood feet away from the throne of a fallen angel. Cas hadn't taken that shit well at all. Of course, that's why she could do it; demons have a blindspot when it comes to the weakest, especially the most powerful ones, like they can't even see them. That may be fine ninety-nine point nine nine nine percent of the time, but Dean knows from experience you always watch for that point zero zero zero one or you're very dead. 

Not that she'll be pulling that shit again anytime soon; the bindings of formal apprenticeship mean she's restricted on where she can go, which is currently 'anywhere not in Cas's line of sight outside the Tower'. Dean figures a couple of hundred years, Cas may lighten up, but he's not betting on it. Unlike demons, he's careful with all his toys; nothing happens to them unless he wants it to.)

"Under Castiel, I thought her education would have proceeded more quickly," his companion adds with a shitty attempt at casual. "It's been a decade and she's still restricted."

"It's almost like making an unconditional deal could one day bite you in the ass," he answers, grinning at her over his shoulder. "Welcome to contract law, sweetheart: the only reason I didn't discipline you for stupidity was because I had to see this play out." Another thing that worked out even better than he thought: Vera didn't dissolve her deal with his lieutenants or with those she was protecting in the Pit. Result: as Cas's apprentice, she's inviolable and therefore they can't punish her for the sins of those pledged to her, his idiot lieutenants can't touch any of _them_ , per contract, and now they're free to do whatever the fuck they want.

(All of whom haven't wasted a second gloating but are getting shit done as well as regularly reporting to her; he's going to be interested who in that group will be next to come to the Tower. He won't admit he has a preference, but that doesn't mean it doesn't exist, or he isn't considering how to make it happen. He's got some ideas.)

"Don't worry about it," he adds, twisting the knife. "Give her a century or two, she may be willing to renegotiate."

"A _century_?" she exclaims, probably thinking about that group, too; she's not completely stupid, though maybe that's wishful thinking. "Apprenticeships never take that long."

"It takes as long as it takes," he answers as Fido and Spot edge closer to Cas's legs, the pup trying to climb over them to see what's so interesting. He focuses on the pup, currently bouncing at the heels of the adults: Fido's latest litter. Only survivor, come to think: it took Cas fifteen generations to produce Fido, the first to hit all Cas's criteria. Of the six breeding next-gen adults they have now, Fido's the most consistent in breeding true, which is basically one pup every ten or so litters. Which reminds him: he should find out who sired this one.

As they watch, the Hellhounds begin squabbling. Vera's gaze jerks sideways, and all three drop to their bellies, heads burrowing against the ground. "Look at that," he says in satisfaction. "Barely half a decade with them and they already obey her. Give her enough time, she'll be able to control a full pack on the hunt."

His companion remains silent, possibly because she can't manage more than five at best.

"Wonder what she'll do with 'em?" he adds, because this is fun. 

As Cas finishes, Vera nods at the Hounds, and they get to their feet, looking a little abashed (they do, actually, know better than to distract Cas). At her gesture, the pup bounces toward her, and crouching, she pets the bony head before picking it up, tucking it against her shoulder as Cas calls Fido and Spot and walks into the grass, manifesting a stick in one hand.

"She's soft on them."

"It's like you've never heard of the carrot and the stick," he answers, watching her quiet the pup with a look, and it settles into her arms. "Nothing and no one can hurt you like someone you love. By the time she's done, it'd rather be gutted alive than see her frown." He glances back, not surprised she doesn't understand--or doesn't want to, which in the end's the same thing. 

Coming to the center of the grass, Cas throws a stick for Fido and Spot, who stare at him incredulously. Okay, didn't see that coming, though yeah, that would explain the stick. 

"He's playing fetch with Hellhounds?" his companion says, sounding exactly like Fido and Spot look.

"Why not?" Curious, he watches Cas call back the stick and take two deliberate steps back and both Hellhounds abruptly start to look panicked. It escalates fast, too: from running in circles to darting around yet never reaching the edge of the perfect circle of very green grass. Finally, they drop to the ground, cowering against the bright grass.

Cas watches them, head tilted curiously, then steps forward and both Hellhounds visibly relax, leaping to their feet and looking around again suspiciously. This time, when Cas throws the stick, they run for it, and Dean bites back a laugh at the reaction of the one who doesn't get it. Petting Fido--Cas's preference is pretty obvious there--he watches Spot before throwing the stick again, and Spot gratefully catches it and returns with his tail firmly between his legs.

He doesn't need to examine the structure to work out what this is doing. "How does he think of this shit?"

"I don't get it," she says flatly, and Dean fails to be surprised but succeeds in disappointment; anyone's gonna be a disappointment after Cas, yeah, but it's like she's trying to make an effort at it. "They can't get out if they don't get the stick or don't try--so what?"

"Hellhounds don't have any imagination." She gives him a confused look. "A guess. I'll let you try it next, you tell me if I'm right." Her eyes widen. "Not that I don't appreciate ad hoc groveling or anything, but any reason you came up here?"

At least she doesn't make the mistake of fucking with him. "I'm wondering if it's worth the risk of spending eternity hanging from a chain."

"Depends on the messenger's good intentions." Every person who came running to tell him Cas was fucking around is there, too. He might have been easier on them if they'd done it for him, and they had, give them that much; that they'd also done it to get rid of Cas and into Dean's bed, not okay. "And not forever: I'd take you down when I needed you. But not a second before then." He grins at her. "Pay or play, sweetheart."

She stares at him for a long moment. "One of your lieutenants has been suborned."

"I know." She looks startled. "By the way, you just impressed me. How'd you find out?"

"He didn't let me read him." She makes a face. "He never lets me, of course, but this time--he stopped fighting too quickly."

"Just long enough to hide something, wow, he's stupid." He searches her face. "What else?"

She swallows before dropping to her knees. "I failed you, Master. I was unaware that he had betrayed you."

Oh, that. Looking down at her, he considers his options. "Get up," he says finally, and she struggles to her feet, clumsy the way she usually isn't. Reaching out, he cups her face, and the wide eyes fix on him, filled with terror and adoration in equal measure. "You didn't fail; he did."

"You appointed me to lead them, Master," she answers dully. "His actions are mine."

"He was always going to fuck us over," Dean tells her. "Only reason I kept him was because he was useful; you were the one who made sure he stayed useful this long. Not bad, by the way."

"There's more," she whispers, starting to shake, but her eyes never leave his. "I think--I saw something in his mind. Something that--he's planning something against Castiel. I came to you the moment I was able to see it, I don't know when--"

"Hold up." Dean turns around and scans the field, then just beyond it: look at that. "That would be now."

It's the least subtle sneaking over the border possible, but if he was fair--he's not--normally this area is exactly where you'd want to try. There's literally nothing here, which is probably why Cas chose it for his latest experiment.

"With friends," he murmurs, tensing: the three with him are Pit, but they're not his, which means his lieutenant been hiding them personally from Cas's purges. He just stops himself from snapping Cas up onto the cliff with him. "Get two of the others you trust and find out who's waiting out there. I'll take care of this."

"Yes, Master," she says, starting to step back.

"Why'd you tell me?" he asks, and from the corner of his eye, he sees her stops cold. "I could rip it out of your mind, but hey, you earned five seconds."

"He's yours, Master," she says, and he can actually hear the centuries-long struggle in her voice. "You're my Master, and he rules beside you by your decree; that makes him my Master, too. That is the only thing that matters."

And here he thought only Cas could do anything new in Hell. "By my will, that which was yours is yours again: your name . Her mouth drops open, eyes wide. "Congratulations, Erica; atonement for fucking up with Vera is done." He grins at her. "Don't approach yet: all I need to know is who it is out there. And don't get caught: I'll be pissed if I have to come get you myself and put you back together."

"Yes, Master," she says breathlessly, worshipfully. "Thank you, Master." Stepping back, she vanishes, and Dean steps off the cliff just as on the side closest to the border, the four idiots step onto the grass and abruptly look confused, because sometimes, everything just works out like that.

"Cas," he says, and Cas turns with a bright smile, Fido and Spot both looking hilariously relieved. "Come here." Without argument, Cas--with both Hellhounds on his heels--walks over the edge and back out, looking pleased with himself as Vera barely catches herself before dropping to her knees, eyes flickering up to him with an expression he doesn't quite catch before lowering her head submissively. "You, too."

The pup begins to wiggle, jumping from her arms when she's almost close enough. Almost: Dean catches it before it hits the ground, holding it up to get a good look. "Look at you," he croons, keeping half his attention on the increasingly distressed looking idiots. Barking happily, it licks as soon as its in range. "My bad, I haven't visited, sorry." Too long, come to think: the last he saw it, it was just a newborn bag of bones and patches of fur barely holding together, because Lilith's work ethic was (according to Cas) really lacking when it came to sufficient gestation. 

It barks its agreement before settling into the crook of his arm. "How's it doing?" he asks, scratching underneath its chin.

"Perfect," Cas answers, sounding pleased. "The imprinting was fully successful and Vera gave it its name. It should select female to match its owner when it comes of age, and with two breeding females, I can eliminate all but the foundation lines for this variation. None of the others have shown this much potential."

He looks at Vera. "What did you name it?"

"Lucca," she answers, smiling at it fondly. "It keeps asking if you were visiting again soon, in case you're curious."

He grins down at it and it barks, revealing dozens of tiny razor teeth. Regretfully, he hands it back. "I'm sending you back to the Tower," he says, and she nods, starting to put Lucca down. "Take it with you: now that you named it, it shouldn't leave your side unless it's ordered to. From now on, everything it needs and wants should come directly from your hand alone, and that includes when it first starts hunting." She nods. "We'll talk about it later."

"Yes, Master," she says, tucking it against her shoulder before looking at Cas, who smiles back, more at ease than Dean can remember since the last incursion on their borders (that was so much fun, they've got to get someone to try again). The near-constant, destructive restlessness is leashed, or maybe redirected would be more accurate; Vera's maybe the only one who can live inside the focused intensity that Cas gives to his projects. She's everything Dean hoped she'd become when he strapped her to the rack and even more: exactly what Cas needed. She'll never bore him, never disappoint or annoy him, never fail him, never betray him, a student worth the Master's efforts to shape her: Cas's perfect material. And if Cas feels the need to give her all his attention, well, Dean can't actually argue; he's doing exactly what Dean taught him.

After she's gone, he turns to Cas, who looks dangerously close to asking what's he's doing here. "She's even better than I thought she'd be." Which is saying something; she's farther along than he expected, too, and he wonders uncomfortably how he missed that, or what else he might have missed.

Cas smiles. "Of course. My Master was thorough in my education; I could do no less." Dean laughs, sliding an arm around Cas's waist and tugging him closer. "Though as yet, I haven't been able to entirely eradicate the instinct to kneel in your presence," he adds with a frown. "Human instincts are difficult to eradicate, of course, but those bestowed here are artificial; they should not be this persistent, especially considering her progress so far."

Yeah, he saw that. "Has she argued with you yet?"

"No, but I haven't been able to bring myself to provide sufficient provocation," he admits reluctantly. "I enjoy spending time with her. If I misjudged her progress, the discipline will have something of a--chilling effect." He takes a breath. "I'll create an opportunity--"

"Don't," Dean tells him, though not because there's any chance he'll lose his new toy. "It's got to happen on its own and she has to choose to do it. Otherwise, the first time you discipline her, she'll never do it again no matter what happens."

"The discipline your lieutenants inflicted on her didn't deter her," Cas argues. "And I certainly wouldn't lower myself to their methods; they seem to confuse 'excess brutality' with 'effectiveness', and fail quite dramatically on the second."

Well, yeah, but that's because Cas has a different standard for 'effective' and also, a different definition altogether. Which makes sense: the best they could do--which by any normal standard is pretty fucking effective, if not particularly sophisticated or imaginative--wouldn't so much as get his attention if he was the subject. As an observer….it'd be like asking Michelangelo or Da Vinci to admire the efforts of a two year old with poor motor control and a broken yellow crayon. 

"Their methods are actually have a start and end point no matter what happens between," Dean tries. "They're effective; they're just designed to actually _end_. Yours start, sure, but just because they have an endpoint doesn't mean they _end_ ; they stick around possibly forever, I’m still testing that." He rolls his eyes at Cas's skeptical expression. "I didn't say they aren't boring as fuck, just that's not the same thing as 'effective'."

Cas looks baffled. "That they seem to find monotony entertaining…."

"Trust me, I know." Though gotta give them credit, Vera definitely offered them some inspiration for development there when they had her. "Look, it wouldn't have mattered what they did to her; she didn't care. No matter what you do, it'll be a hundred times worse, because you matter to her. She has to decide to do it, take the discipline, and then be willing to do it again knowing the consequences." He remembers her expression again and thinks he knows the problem now. "She's afraid of me."

Cas frowns. "Of course. She'll never not be."

"This is the wrong kind. The only thing that got her into the Tower in the first place was you and she didn't expect to survive," he says flatly, barely controlling the rising anger at the memory of how she looked at Cas, how he looked at her…what the fuck is wrong with him? "I didn't kill her--I fixed her, for fuck's sake!--but she's still there, waiting for me to destroy her just because I can." 

"She was in the Pit for all her existence here," Cas says reasonably. "You are Chief Torturer of Hell and Master of the Pit, but most importantly, you are _her_ Master, and for all her remembered existence, had always been and would always be. Her memories from before are a very small part of her existence in whole now, and they can't simply erase all she has experienced since."

"She's not like that around you," Dean says hotly before he can stop himself, knowing how stupid it sounds, like he doesn't know how this works.

"Of course not; she's my apprentice," he answers, even more reasonably, like that's supposed to help. "The requirements of formal apprenticeship assure there is nothing she is that I do not know, but for me to fully shape her to my will, her obedience alone is not sufficient. She must know me as well, so that I may teach her to want only what I desire for her. The process takes far longer than if I were to utilize cruder methods, but what is created will be without flaw, and I will accept nothing less." Then, "Or so my Master taught me."

"Don't even," Dean warns, because yeah, he does know that. It was something neither Alistair nor his successor ever understood, which is why Alistair's rule ended on earth after capture by an angel from fucking _Heaven_ and Dean defeated his predecessor and the armies of three territories with an army he recruited from the Pit itself under the fucker's very nose, among its officers the fucker's own lieutenants, and led by Cas.

(Not that he needed an army when he had Cas, but he was making a point. And hey, they were useful for the clean-up after.)

Fear and obedience are useful, but they're just tools, and like any tool, given time, given pressure, they can break. He's the one hundred and fifth undisputed ruler of the Pit, taking the Throne by both right of succession and right of conquest, and his rule isn't just among the longest in memory; he's also the first Master since the First whose rule has never been formally challenged from without or, most importantly, from within. His lieutenants can't be suborned (except the ones he wants to be), his officers can't be bought (not after being broken and reformed by him and Cas), his armies are entirely beneath his (read Cas's) hand, and even the smallest incursions at his borders are paid for tenfold. He barely has to do a thing, to be honest; this is the Pit of Hell, and it and those within have knelt to him the way they've knelt for no one and nothing else since the first Master Ascended its throne.

Of all the territories of Hell, the Pit is the closest to the purity of chaos, nearly untouched by angels and their need for order. It first formed not by the deliberate claim of a single ruler but to isolate the inhabitants from the more well-ordered territories ruled by pet demons beneath the hand eye of the rulers of Hell and their too-delicate sensibilities. The Pit is where the greatest mass of raw humanity still resides, both on the rack and in the newly broken souls still too weak to escape the squalor, alongside demons so old and so mindlessly brutal or monstrous that they had to be driven from other territories when they were too strong to destroy, and the meat of the Pit, demons that were nothing and never tried to be anything else. The borders of the Pit have always been as uncertain as the vastness of the territory they encompass; more than one who claimed to rule never left the confines of their stronghold within the capital city, and even Dean can't honestly say they didn't have reason to be wary (though that's no excuse). There's no way to estimate a population always in flux, from newly-damned human souls to demons older than the existence of any territory in Hell, whose breaking was accomplished when angels still administered the rack.

Rule of the Pit belongs to the strongest, the most powerful, the most ruthless, the most determined, the most skilled, and not unrelated, the most sadistic; there's a reason the Chief Torturer of Hell was the first to formally claim the Pit in its entirety as her domain, taking the personal submission of every demon within before Ascending its Throne, and her rule lasted a thousand years. She built the capital city from which she ruled, set the borders of the Pit and guarded them jealously against incursion, and personally instructed every demon beneath her hand before they were allowed to administer the rack. She chose her lieutenants not from the minions cluttering the angelic courts, but from those broken on the rack by her hand alone and personally shaped to her will and trained in all of her skills.

While Chief Torturer of Hell and Master of the Pit aren't actually synonymous, as it began so it goes on; no one less could hope to demand the obedience of the Pit and get it and no one could match the strength or the skill of the one the Pit called Master. Technically, angels still have the right to appoint the Chief Torturer of Hell and can give the job to anyone they want without regard for the laws of succession; in practice, accepting the appointment without also having claimed the Pit is a very convoluted but guaranteed way for your existence in any perceivable (or maybe usable?) form in Hell to come to an abrupt end, and that's not actually easy to do. Souls, unlike a human body, don't have an expiration date, aren't subject to decay, and you can't actually destroy one entirely forever. Which just means you gotta adjust your expectations when getting rid of someone to 'as long as possible' and get creative in deciding how to make that happen.

(Dean's never really seen the point of that; sure, it's fun for about five seconds but then it's over. Making them kneel though…that's forever, and you get to see it any time you want. Not to mention the waste; if others want to destroy their own base, let 'em. He can recall anyone he's purged or destroyed with a thought, ready and willing to serve (and grateful: pathetically, deliciously, ecstatically grateful, and that also never, ever gets old).)

It's been millennia since any angel tried to exercise that right beyond making the new Master come to them for confirmation along with taking their formal submission before the most powerful demons and the rulers of every recognized territory in Hell. Traditionally, unless you were a suckup from the oldest territories or one of their fucking pets, you dragged that shit out until you got a formal summoning (that, as it turns out, really is impossible to disobey). Upon his Ascension, when Dean received his formal invitation to present himself before them, though, he didn't fuck around making them wait any longer than it took him to give his lieutenants their orders, put Cas under, and lock down the Tower (not that if Cas came to, that would do shit but maybe slow him down, but if his lieutenants were stupid enough not to get out of his way, he really didn't care). It's not like he was looking forward to groveling for a straight fucking month on icy-white marble floors (seriously) among pristine marble columns (no, seriously) under the noses of every angel and half the demons of Hell, but he couldn't risk any rumor of how he conquered the Pit getting back to them before the appointment was formalized and his submission was made. 

It's not that they couldn't kill him after that--part of your submission is verbally acknowledging their right to do just that but with way more words interspersed with pauses for recreational groveling--but see angelic sensibilities and their thing for order; they can, but as long as he plays inside their rules, they _won't_. That much he proved the day Cas first joined him on the Throne, and giddy, he realized it wasn't just a maybe anymore; one day, he was going to take the submission of Hell itself and sit on its Throne in his own right, and Cas was gonna be right beside him.

If Hell really thinks he's only working from the old playbook of Alistair and Africanus and Leviticus and Selev to get these kinds of results, this is going to go way faster than best case scenario. If there's any playbook he's borrowing from, it's the First's, and he thinks she'd approve of his updates.

"It takes time to adapt to the change in circumstances," Cas continues. "Vera simply needs time, Dean. She doesn't know you yet."

And that, Dean realizes, is the entire fucking problem.

"I'm surprised you even noticed her," Cas adds casually as if in emphasis of the fucking obvious. "Apprentices usually bore you, especially ones this early in their training."

"With my lieutenants, yeah: they make shitty picks," he says defensively, but Cas is right; he hasn't noticed her. In fact, thinking about it, he can count the number of times on one hand that he's seen her since her apprenticeship began when he didn't summon her himself. "Yours, not so much."

Cas starts to answer then stops with a frown. "Is that why you're here now? Not that I object to your attention," he adds. "But I thought you were with your lieutenants."

Right, that: talk about being distracted. Glancing at the idiots inside the lawn still, he checks in with Erica; she's almost there, good. "Quick question," Dean says. "Why'd you decide to do whatever this is here?"

"This is the most remote and therefore the most vulnerable of the Pit's borders," he answers, like that's not a very good reason for him to stay far, far away from it. "If this works, it should--distract--anyone who tries to cross the border against your will and hold them here without damage, to be retrieved at your pleasure. Battle is all well and good, but there's no reason not to add variety to our defenses."

Dean keeps his gaze firmly on Cas, but wow, those demons are starting to look seriously freaked out, which isn't easy to do to with demons, even shitty ones. What he's not sure of is exactly _how_. "So you're, what--using their own minds, right?"

Cas smiles in pleasure. "You watched Fido and Spot?" Dean nods. "I had to implant several suggestions in the design for them. Demons have more imagination than Hellhounds--the latter having none--but that's not saying much, so there are some specific additions for them as well."

"No one's up to your standards," Dean says, grinning despite himself and tightening his hold. "Just suggestions?"

"Only in the first draft," Cas answers, leaning against him. "This version also includes an element of escalation; it encourages them to imagine how it could be worse, and worse it will immediately be."

Dean kisses him: only Cas. "Goddamn amazing," he says against Cas's lips. "We're definitely using this."

"I haven't tested it on anything but Fido and Spot," Cas protests. "It seemed effective, but…." Dean glances at the field and Cas follows his gaze and frowns thoughtfully, watching as they start to panic. "Oh, interesting. Did you bring them?

"Nope." Dean glances toward the border and feels Erica's triumphant confirmation and orders her to call in his other lieutenants and keep them surrounded but not approach, not yet. "Two of your Brothers' toys are out there." Before Cas can look, Dean tips his head up and stares into the blue eyes, looking at the whole reason he followed Cas out here today. "Pay attention, Cas. The reason I'm here is that you're blocking me."

Cas's eyes widen, and Dean just manages to keep his temper in check; there's no way Cas could have known he was never, ever supposed to do that. He's never had to discipline Cas for anything he didn't do deliberately to piss him off (that's just good fun, come on), and fuck if he'll start now.

"Tell me not to look and I won't," he says carefully, holding Cas's eyes. "I love surprises. But don't ever block me."

"I'm not--" Cas stills, not a good sign. "I'm not doing that. I would _never_ do that. I thought--I thought you must have done it so you could watch without me noticing. That's why I was surprised you were here."

Fuck: now this is a problem. Turning, he puts himself between Cas and the border and examines this area and then the entire Pit and can't find anything. The laws of contamination still apply, and Cas is--technically speaking--still an angel, no way around that. So how would they use that to get him over the border....

"I can't feel the lawn anymore," Cas whispers. "I can't feel the Pit, or you--it's as if you're no longer here. What did they do to me?" Dean brushes a calming kiss against his forehead as the Pit begins to tremble around them. Normally, that'd be a little worrying (not that he doesn't love Cas's extempore renovations, but it's been a while since Cas did it on accident), but right now, he's all for it; whatever they did to him, the Pit can still feel and respond to Cas just fine. So something out here is doing it and it's specific enough to affect Cas but not anything else: that narrows it down. "Dean--"

"Give me a second," he says as the Pit upgrades to a low-grade quake underneath them. Angels don't have new ideas, and there's only one thing that would hit Cas like this; the only surprise is that he didn't sense it. As Cas's fingers tighten in his shirt, Dean turns his attention on the four idiots and concentrates; there we go. Grace from outside the Pit would be enough to notice when it locked him out of this area (and Cas while in it), but the tiny bit of Grace in those four, while not enough to pick up individually, together and in proximity to Cas, would block him from the Pit, at least temporarily. If they got close enough to him, boxed Cas in, the four together would be just barely enough that one snap from his Brothers through one of their pets outside the border would take Cas right over it before Dean or the Pit knew it happened until they sensed his absence and it was almost too late. 

Almost: he's not stupid (though they apparently are if they thought any of their pets could hope to survive what would happen if this had actually worked).

"Look at me." Meeting the blue eyes, he studies it again, carefully following its trail and marking how they did it. "It's fine, easy to fix." And it'll never happen again: he can see in Cas exactly where he needs to do some more work.

"How--"

"The four idiots currently--doing that." Dean bites down in amusement at the reaction of one of them: he's got to see what the fuck that is. He's always open to new ideas. "Did I ever tell you I love your work?"

Cas's mouth twitches reluctantly. "Thank you, but you might say that's their work. Now please _fix this_."

"I need to do something first. Can I go in there or do I need you with me?" Cas wouldn't be above fucking with him and honestly, he regrets missing it if that was the plan. _Tabula rasa_ would have blown his mind, and anyway, Cas loves surprising him and he hates disappointing him.

"You can," Cas answers. "I thought you'd find it next time you took your lieutenants to patrol this border and would find their reaction amusing."

Dean kisses him; that would have been hilarious. "Oh, I'm definitely doing that. Wait here." He gives Cas another kiss when he tenses unhappily. "The block's nothing: I'm always with you, just like I promised." Even if they'd gotten Cas out, which on a guess, they wouldn't have expected either.

Licking his lips, Cas nods, but the tension doesn't ease; it's not that he doesn't know it or believe it, he just doesn't like it, especially with fucking angel-toys this close. Spot whines in confusion, but Fido moves closer, shifting her body to press against Cas's legs and between him and the lawn, a low growl reverberating through ground beneath them. 

"Good girl," Dean says in approval and steps onto the law.

Inside, it looks just the same as outside--a perfect suburban lawn, Pit all around--but when he focuses on what's happening to those demons, he can't help grinning: yeah he's definitely trying that the next opportunity he gets. Almost regretfully, he snaps his fingers, ending the scenario and watching everything unmake immediately, leaving them exactly as they entered, completely undamaged: nothing to fix for later fun and games, it's great.

They stare at him in recognition and slowly growing horror, and it says a lot (awesome things) that he still scares them more than anything, even--well, _that_. Fast recovery time, too: just keeps getting better. "Master…." His ex-lieutenant starts. It's almost tempting to hear what he comes up with, but hey, he doesn't need to talk for Dean to find out.

"Kneel." They hit the ground, and Dean decides against subtlety. Effortlessly, he pulls each of their minds open and guts each one, getting the entire plan and seeing if he was right about how this would go down; no surprise, he was, but it also tells him just how much he missed. One of them has been following Cas every time he leaves nospace. This little project was their first and best chance and they took it. Erica's suspicions got them moving, but they hadn't expected her to act immediately if Cas was the target; fair enough, that surprised him, too. 

The whole thing pisses him off, but it adds an extra something they also fucked up Cas's surprise for him. Carefully, he puts their minds back together good as new; sure, it takes time, but Cas deserves to have his newest toys in mint condition to do their duty as test subjects. 

"I wonder if you can possibly imagine what I'm gonna do to you when you get out of here," he says as they sway uncertainly. "I gotta top whatever happens here, so honestly, can't wait to see what you come up with." He smiles at their terror. "See you then."

Walking back out, he snaps his fingers, restarting from the top and setting the whole area for observation only, then reaches for Cas, keeping half his attention on the border. "I gotta see the design," he tells Cas. "Deep breath: this will only take a second." Meeting the clear blue eyes, he checks one more time and finds the block again, easing between it and Cas and follows it to the source, holding them both in his mind. All at once, he takes apart the block and pulls in the entire Pit to blow everything straight where it came from; from what he can tell, that hurt. Cas sucks in a startled breath, relaxing against him as Dean cleans the remains from his mind then shows him what he got from the four idiots' minds . "Your Brothers needed mules: they provided. It won't happen again."

Cas closes his eyes, head dropping against his shoulder. "You're sure--"

"Really sure," he says soothingly, threading his fingers through the dark hair, and sends a command to Erica: _take them, gut them, and stake them in the Pit for whatever wants them_ , then pauses, remembering where those pledged to Vera are currently hiding. Even gutted and staked, these four would usually only be meat for the very strongest, but they've trained themselves to always hunt together and share what they take, going against every instinct a demon has. It'll still be a challenge for them, but if they can resist the temptation of fighting each other when faced with this much power and work together, they'll each have more than they've ever had access to since they got here. He show Erica where he wants them staked. _There. Leave as soon as you're done and don't return until I order it._

"Can the idiots leave?" he asks Cas when they start staking them out; that's fun to _do_ , yeah, but boring as fuck to watch.

Cas lifts his head. "Of course," he answers with a ghost of amusement. "Anytime they wish. It's quite simple; all they must do is not let themselves become distracted while trying to escape."

And Cas once seriously believed there was something _wrong_ with him. "Let's start with a week and see what happens. I'll send Erica to check 'em daily, see how it's going."

"Erica." Dean shows him what happened on the cliff, and Cas tilts his head, eyes unfocused, before he nods. "Tell her by my will she's excluded from the effects if she wishes to enter and observe. She can decide if she wants them to see her or not. Her observations will be useful in perfecting the design; I'll expect her to report those to me in full."

Dean raises his eyebrows as he passes the message, amused by her unconcealed surprise. "Huh."

"Her loyalty to you is without flaw," Cas adds, looking thoughtful. "How she interprets and expresses that loyalty is what is at fault. It is possible her flaws can be corrected, should she choose to see them."

"Question is, will she ever see them." A question for the ages. Giving some final instructions to Erica, he dismisses everything from his mind but Cas. If he'd ignored that sudden blankness and decided to talk about it later instead of coming out here to see what Cas was up to, if Erica hadn't warned him--yeah, Cas's lawn took care of the immediate threat, but that's not the point. Cas shouldn't have to tell him anything; this is Cas. Dean should already have _known_. "I haven't been paying enough attention to you," he says abruptly. "And don't say you don't mind," he adds when Cas frowns. "You do. Why didn't you say something?"

"I understand," he answers for a long moment. "You have more important concerns, and I can certainly keep myself entertained in your absence."

Dean stiffens: that sounds way too familiar. "As of now, you don't leave my presence for any reason without my express permission," he says, tightening his hold on Cas's jaw when he frowns, just short of shattering solid bone. "Do you understand? Say it."

The blue eyes go blank. "Yes, Master," he answers flatly in formal (read: pissed) acknowledgement; fuck his life, if this means constant random prostration and 'Master--" prefixed to every fucking sentence…. "May I ask for how long I am to be so restricted?"

"Assume the foreseeable future for a start," he answers. "Don't look like that; I'm not locking you up. You want to go somewhere, tell me; I'll take you."

Yeah, that didn't help at all. "May I know what I did to earn your discipline, Master?" he asks in the same flat voice, and Dean can almost _see_ him debating when to drop to his knees and grovel in a thousand separate, obnoxiously submissive positions; he's probably making a priority list. "I would beg to be permitted to offer my atonement for denying your will--"

"You didn't--" He stops himself before this gets any weirder (and before the groveling shit starts, please). "You're mine; I'm entitled to anything I want from you, and right now, that includes your constant presence at my side."

"I've never denied you anything--" 

"You said I had 'more important' concerns," Dean interrupts. "Don't tell me you didn't mean it; you did. So how are you entertaining yourself, sweetheart?"

"I've done nothing in your absence that didn't have your formal approval," he answers with a slow smile. "You chose my entertainments personally, in fact. You certainly have the right to discipline me for obedience, but a Master without discipline of himself is nothing more than a beast. I don't have the right to demand your attention--"

"You don't have any rights but what I give you," Dean tells him. "That's one of them."

Cas's eyes flicker up. "I know."

"You don't," Dean answers, "if you thought I wouldn't be there when you were experimenting with Lucca's parentage if you wanted me. Or when you're teaching Vera, for that matter; I didn't even know she'd named it." Then something else occurs to him and the rush of jealous rage drowns everything beneath it. "Did you?" he whispers, closing his hand over Cas's throat. "Want me there?"

Cas's eyes widen. " _What_?"

"You think I gave you Vera to replace me?" he asks softly, already planning what he'll do to her for Cas even _imagining_ that she--or anyone, ever--could do that. Even the possibility--

"If you would like me to renovate the entire Pit," Cas answers coolly, "you need only ask. My control has improved substantially; what part would you like me to destroy first?"

Through the fog of rage, Dean's aware this went sideways. "Cas--"

"Choose, or I will for you," Cas says, way too calm, and the anger is almost washed away at the utter stillness around them, a sense of something waiting; it's really familiar and the Pit is paved in red reminders. "Very well: I'll start where your lieutenants currently abide--"

"Kneel."

Cas drops to his knees without hesitation, and Dean takes a deep breath, making himself stop and think. He sends a warn-off, but honestly, he'd almost welcome someone wandering close enough to see. Walking over, he gets Cas's chin, tilting his head up. "Yeah, fine, my bad: I shouldn't have said that." Cas looks back without expression. "You get I didn't mean it, come on."

"As you will, M--"

"Say 'Master' and I will rip you apart," Dean interrupts, jerking Cas's head higher. "You done with the drama?"

"Are you?" Cas asks flatly. "You know perfectly well I'm doing nothing objectionable and as you can't possibly be jealous of Vera merely because I enjoy her company, why…." He trails off, looking so genuinely surprised that Dean's remaining anger dissipates into--something that he doesn't think he wants to identify. The blue eyes search his face, like he's looking for something. Then, "I beg forgiveness," Cas says quietly, leaning into Dean's hand, and Dean gets the distinct impression that whatever Cas was looking for, he found it.

"It wasn't your fault," Dean says stiffly, brushing Cas's hair back. This is ridiculous; he _knows_ Cas wouldn't--he wouldn't. "You--"

"I should have known," Cas corrects him, turning his head so his lips brush Dean's palm, and Dean wonders what the fuck just happened. "Perhaps you'll allow me to perform a less--formal atonement?"

"What would that be?" Dean asks warily; you wouldn’t think studying would be something he'd need to do here, but as it turns out, boy he was wrong.

"There's not one…yet," Cas answers, tongue sliding up the center of Dean's palm before looking up at him, pink lips wet. "Your assistance in its creation would be invaluable."

That's the best idea he's heard possibly ever. "Yeah," he says, staring to lean down to that tempting mouth and realizing belatedly there's other options here. "Get up."

"Your will is my life, Dean," Cas agrees. "However, may I first have clarification on the terms of my discipline?"

What the fuck is Cas talking about? "What--uh part?"

"All of it."

Fuck his life: closing his eyes, he takes a deep breath. Right, _that_. "You don't leave my side. Anywhere I go, you're going to go with me. You want to go somewhere, I'll take you. You need to do something, I'll go with you. The only way you can leave me is you ask permission from me and I say yes, and spoiler: won't happen. Anything else?"

"What if there is something I want?" Cas asks curiously. 

"Then I'll get it for you." Stepping closer, he looks down into Cas's eyes. "There's nothing you need, nothing you could ever want, that you can't get from me. You can have anything you want, but only from me. If you ever turn to anyone else for _anything_ \--"

"You won't discipline me," Cas says in a completely different voice. "Instead, you'll torture them for me while I watch. Then you'll fix them, so you can make them watch you with me, so they know how much I want you, that their purpose now, their suffering, only makes me want you more. Then you'll banish them to their chains and forget them until I remind you, and you'll call them back and do it all again."

Dean threads his fingers through the dark hair. "That'd be it."

"Then I must assume my discipline now is indicative of how much you want me," Cas adds unexpectedly,. "I accept your terms."

Dean grins and extends a hand, pulling Cas to his feet. "Took you long enough. How close were you to a full fucking prostration?"

"I was considering performing a Formal Atonement," he admits thoughtfully, and Dean just stops himself from shuddering; his predecessor really got off on those, which combined 'mediocrely gruesome' with 'boring as fuck' and went on for-fucking-ever. It wasn't even creative, for fuck's sake. On further consideration, before he and Cas took over, that shit probably qualified as the height of entertainment; he should think about asking his predecessor one day about that. "I missed you," he adds. "Sometimes, I wonder if reassuring you regarding my fidelity was a mistake. As a method of gaining your undivided attention, it worked without fail."

You don't say.. "You could have just said something."

"I shouldn't have to." Dean starts to argue, then stops himself. "If you deny me what I want, I must assume that you have reason, and it's beneath me to beg for what you have decided I cannot have. That doesn't mean I won't show my displeasure."

"In other words, it's my fault?"

"The alternative is to assume you're so stupid that you don’t know you're the only thing I want," Castiel answers, and okay, that's fair. "So yes. You have partially rectified your neglect with your order that I not leave your side without your permission, which I appreciate very much, as that also mean you cannot leave mine."

Dean blinks. "Wait, what?"

"Under the terms, the only way I can leave your side is for me to ask your permission to do so and you agree; that is the single method by which we may be separated by your will. In contract law, any ambiguity favors the other party: in this case, me, and that is my interpretation. Therefore, unless I request to leave you and you agree, you cannot leave my side any more than I can leave yours." His eyes narrow. "The fact you considered that a form of _discipline_ , however…."

Cas knows natural law like he breathes, and contract law is only a small part of that: he can't be wrong, literally. Dean doesn't pretend he'll ever have Cas's sophisticated understanding of the ins and outs of terms, but that doesn't mean he hasn't learned a few things. "Since when does discipline have to be punishment?" he asks, sliding an arm around Cas's waist and drawing him closer. "Sometimes, it's just fun for everyone, ever think of that?"

Cas smiles. "As you wish." He tips his head. "Does this mean you wish to take a more active part in Vera's education?"

"Why? You couldn't do it wrong if you tried. Hold that thought." Waving Fido and Spot away to hunt, he opens their room in the Tower around them and feels himself relax just knowing no one and nothing can get Cas in here. "You don't need me for her."

"I always need you," Cas corrects him, dropping onto the wide sofa. "I think you will enjoy her a great deal. You never took another apprentice after me--"

"And I never will." Teaching Cas during his apprenticeship was incredible, like getting high every goddamn day, and it's only gotten better since. "Even if I wanted to, what would be the point? I'd probably purge them before the end of the first day in sheer boredom. If you didn't destroy them first, that is, and I wouldn't take bets on that."

The blue eyes flicker for a burning second. "I brook rivals no better than my Master."

"Well, yeah." It would be pretty fucking epic, no lie, and might even be fun, but so not worth the bother. Joining Cas, he cocks his head. "Okay, why would I enjoy her?"

"She's mine," Cas answers, like it should be obvious. "I should have recognized what was wrong before today," he adds, lazily sitting up before straddling Dean's lap. "It upsets you, how she reacts to you."

He sighs, sliding his hands down Cas's thighs. "It shouldn't," he admits. "But yeah, it does."

"That can be easily corrected; she must know you and all that requires is your presence," he answers, resting his arms on Dean's shoulders and peering down at him. "Assisting in her education will speed the process considerably."

Dean tips his head back against the couch. "You think that'll work?"

"I know it will." Cas leans down, and Dean is perfectly happy to forget everything but Cas's warm mouth and the feel of him in his lap.

Then Cas pulls away. "What--" Dean starts, then sees what Cas is watching: Erica just crossed onto the lawn, not even hesitating--gotta give her credit for courage there--and walking toward the test subjects. With a touch lighter than Cas has ever bothered to use with any of Dean's lieutenants, he slides inside her mind and when she doesn't flinch--or at least, not much, not bad at all--Dean follows and starts to grin at what she's watching. "Holy shit," he breathes, feeling Cas analyzing the design for flaws. "Dude, you're not going to find one, so stop and enjoy this."

True, it's like a low budget version of one of Cas's earliest installations--pure butchery, no artistry, not even a little _style_ \--but all the salient points are recreated almost perfectly. Probably need the experience of being an installation to get the finer points, now that he thinks about it. "This is awesome," he says, examining the structure with half his attention; how the fuck does Cas _think_ of something like this, much less make it happen? "This their idea or yours?"

"In the absence of imagination on their part, it uses the most upsetting or traumatic experiences they've experienced themselves, witnessed, or learned of, in that order," he says, sounding distracted. "Should that be insufficient material, I added simplified forms of my own work, but I didn't expect there would be need for it. Even the Hellhounds didn't require me to _tell them_ exactly how to suffer; mere suggestion was sufficient."

"In other words, they're wasting it," Dean interprets, not surprised at all. "Remind me to get you better subjects."

"This iteration was simply a prototype," Cas answers dismissively, but Dean can hear the discouragement in his voice. "They aren't taking advantage of its range for escalation or mitigation at all. If I wanted to watch substandard reruns of my own work--well, I don't. This is embarrassing to observe."

"It's perfect," Dean assures him. "Your Brothers have a type in their toys, come on." Cas wrinkles his nose. "Being in there can't do anything but help."

"I live in hope. Until then…." He feels Cas's attention shift to Erica, and while she stiffens, for the first time, she doesn't fight it, something no amount of discipline so far had managed to put a dent in, so color him impressed. "Erica, they require inspiration. Can I trust you to see to it?"

Warily, she forms a concept and offers it for examination; it's also based on one of Cas's installations, but way better, like she actually gets what they're supposed to be about, and then--even more warily--her own interpretation. It's genuinely interesting.

Cas smiles. "Lovely," he tells her, and Dean just manages not to laugh at her not-hidden-fast-enough shock. "I'm impressed with your creativity; please continue to exercise it. The field will accept your suggestions now; you're released from your other duties for the duration of the testing period. Report to me daily." Then, "And do enjoy yourself."

She offers her gratitude and submission, dazed under the force of Cas's undiluted approval--something Vera responds to like a junkie to their drug of choice--and Dean's grinning as they withdraw "Look at that," he says softly, sliding his hands under Cas's t-shirt and skimming his fingertips over the warm skin. "Didn't make her scream even once."

"I did nothing different," Cas answers defensively, adding at Dean's raised eyebrow, "other than treat her as I do Vera. Obedience is expected, but compliance is more--complicated. It does not consistently respond to the subject's own will, and discipline is largely ineffective and can be counterproductive. Rewarding each instance of compliance seems to yield the best results. Withdrawal of that approval then becomes a discipline in itself, and its effectiveness is extraordinary."

"Give 'em a good enough carrot, they'll make the stick all by themselves," he agrees. "Do it right, and what they'll do to themselves for you will be worse than anything you'd actually do." He grins. "I told you, you couldn't do this wrong if you tried."

"I understood what you taught me in theory," Cas says, frowning. "But watching the effect on Vera has been educational. I don't remember why I thought it didn't make sense."

"It doesn't, not until you get someone you want that from," Dean explains. "With them, though, it's the best part." He sighs, resting his hands on Cas's thighs. "So that informal atonement thing--"

"I just realized," Cas interrupts, "that I forgot to inform you of the progress of my breeding program."

Dean blinks, staring up at him. "Seriously? You want to talk about this _now_?"

"You seemed impressed with Lucca, so I thought you might be interested in its lineage," Cas answers reasonably.

Dean sighs. "Fine, which one sired it? Was that their first litter with Fido?" He may only know the basics of what Cas is doing, but even he can see that Lucca's something special. 

"Second litter," Cas answers. "Lucca was the first survivor, however. I was surprised by Lucca, to be honest. In retrospect, the failure of the first litter was doubtless due to the sire's reluctance; it was much less difficult the second time." Dean gives him an interested look. "In Fido's presence, I gave it the instincts and conditioning of a male Hellhound and let nature take its course when she went into heat. Hellhounds are strictly matriarchal, so success was inevitable."

Dean pauses, startled; okay, didn't see that coming. Or even know it was possible, so he's learned something new and very, very cool. "Who did you use?" And what did they do to make Cas decide they needed some time under a female Hellhound, especially a breeding one. Lilith didn't fuck around making her feelings clear where males belonged in the scheme of things; female (or female-identified) Hellhounds survive adolescence four times more often than their male counterparts, and only half of the surviving males make it past their first experience with a female in heat whether she's breeding or not.

(Watching a female Hellhound go into heat isn't something you forget, and boy, he wishes Lilith was still around, because he has questions, a lot of them. In other words, he almost feels sorry for the fucker who pissed off Cas enough to send him in there.)

"Did he know what was happening to him?" Dean asks curiously.

"Of course; it was aware of everything," Cas answers in satisfaction, "The instincts of male Hellhounds are impossible to resist, however, especially when exposed to a female in heat." Dean grins, settling back. "I reverted it once Fido was successfully impregnated to discover how it responded to the experience to aid in replicating it with others. When it had recovered--which took some time, admittedly--I tried to explain it should consider this duty superior to existence on a chain. Curiously, it did not agree at all."

"Wait, what?" _It_ , not he: _oh_. "You got one of _them_?"

Cas nods hopefully. "I didn't think you'd mind."

Dean starts to laugh; he only wishes he'd thought of that. "Not even a little. Which one did you borrow?"

"It wished to replace you on your throne as well as in our bed," Cas answers casually, and Dean is consumed by a rush of sheer, mindless rage, as fresh now as the day it was dragged before him. It didn't just want to fuck Cas; it didn't even really want the Throne; it wanted to _keep_ Cas, to take Cas _away from him_. Nothing he's done to it--and he's made an effort--has so much as touched that rage; there's no pleasure, no satisfaction, just anger every time he thinks of what he ripped out of its mind each and every time he has it; how it looked at Cas, what it wanted to do to him and still does. It shows him everything it thinks, of it with Cas, things they couldn't possibly have done, that Cas would never, would never, would _never_ ….

"Where is it now?" he asks softly, aware Cas is watching him closely, but he can't concentrate enough to care why.

"I returned it, of course, at least until Fido goes into heat again. She was very unhappy about that, however," Cas adds, resting his elbows on Dean's shoulders. "She enjoyed its attentions very much; its abject submission to her was apparently very pleasing. And unlike male Hellhounds, she didn't have to be careful with it at all."

Dean meets the blue eyes and makes an effort to keep his voice even. "When were you going to tell me about this?"

"When my work on it was complete, and Fido was ready, of course," Cas answers, sliding half off his lap before Dean can ask what the fuck. "Which should be fairly soon. I would not present you with a gift half-done."

"What--" he starts, then Cas snaps his fingers, and Dean blinks at the filthy, skeletal bundle of blood and wisps of flesh appearing on the platform in place of the rack, the entire area bathed in light. It sits up, and with a gesture, Cas restores its condition to pristine. Dean feels his hands clench into fists: yeah, he remembers this one.

"What--" it says, pushing itself up, then stops, staring at them, cringing, but when it sees Cas….

"None of that, Spado," Cas says, and the thoughts stop as if turned off. "Sit."

It obeys instantly, and staring at it, Dean puts it together. "You--"

"I needed time to assure my alternations were successful and complete its training," Cas says, head tucked against his shoulder. "You may speak, Spado. You may even use words."

"Please," it whines, starting to sob. "Not this. Please, not--"

"Silence, Spado; your whining is boring. Fido goes into heat soon, and you don’t want to disappoint her, do you? I would not be pleased." It's horror is overwhelming, emanating in soothing waves through the Tower. "While we wait, you should show your Master how well you can perform and your pleasure in pleasing me. It's the only thing you want to do, after all." He snaps his fingers. "You may begin."

The wide smile that spreads over its face is genuine as it starts to run, ass waving like it has an actual tail; it's like watching a youtube video of the happiest dog in the world, just--not actually a dog. Dean drags his gaze away to look at Cas. "You made it _like_ it?"

"I am not so crude," Cas answers, rolling his eyes. "The instincts are the only addition; it's pleasure is its own, and none of my own design. Seeing how well it performed for me--and Fido--when thus, I chose not to interfere. It did not appreciate my mercy, however; when I release it, it begged me to make it stop. I did consider it, but of all I could do to it, that one thing I could not; those were the terms, it seems, and even I can't break those."

Dean's eyes are drawn back to the platform as it plays a game of imaginary fetch; he can almost see the ball. "Terms? What terms?"

"When it came to me and offered itself to me and indeed, the very Throne itself, should I allow it to have me," Cas answers, and Dean looks at him, startled by the venomous edge. "I then asked it if it would do anything to please me, and it said that it would, that nothing else would give it pleasure, for all of time." Cas tips his head to look at Dean. "Then I gave it to you for your judgment and forgot all about it. I apologize that I didn't inform you of its grandiose promises, but it's not as if it was memorable even in its presumption."

Dean shuts his mouth as Spado roll over with the same wide, inane grin. It literally made it's own carrot _and_ stick, all by itself.

"However, it does have the distinction of being the first I tested on its promise," Cas continues, blue eyes flickering to Dean before he straightens. "I was only waiting until Fido was ready to go into heat again so you could see the finished product in full; you know I prefer not to show you what is only half-done. Do you like it?"

"You…." He gives up, pulling Cas into a kiss, because seriously, what can you say to something like _this_? Thanks just doesn't cut it. "You knew," he realizes. "How long--how did you--"

"I didn't, not until after Lucca's conception," he answers. "When I completed the reversion, it showed me its mind in hopes that would buy it mercy. When I saw…." The blue eyes chill. "I took it apart, of course, and found it all, and what it used against you in defiance of your correction and your will."

Dean lets out a slow breath. "I knew it wasn't real," he says quietly. "I _knew_ \--but it didn't matter. Not when I was with him. It always felt real. Even after, it would _stick_ , and I couldn't…."

"This is Hell; a lie holds as much power as the truth, if not more, provided one is strong enough to believe it utterly. It was very strong; it was quite gifted, in fact, though nothing compared to me, and from me, it's ability could not be concealed, nor what it chose to do with it." Cas's gaze flickers to Spado, adding softly, "I can almost forgive the stupidity of attempting to manipulate me--did you truly think you stand against _me_?-- but not the waste; to have such talent and not use it to serve your Master is unforgivable. To use it _against him_ , however…." The faint thrum beneath them isn't quite a warning, Dean realizes; it's reacting to the memory of that day. Just the _memory_.

"Cas," he says mildly, and the blank blue eyes fix on him for an endless moment before Cas makes an effort and lets out a slow breath. "Lost your temper?"

From Cas's faintly annoyed look, yeah, and if the Pit's reaction is anything to go by, it was pretty fucking apocalyptic, to say the least. "I remade everything. I think."

Dean can't even work out what he's more pissed about now; that it was fucking with him and he didn't realize it, that it tried to fuck with Cas--so not okay--or that it upset Cas enough to make him lose control. And Dean missed all the fun. "Show me later and I'll check," he says casually; sure, he could find out from the Pit, but Cas went above and beyond hiding it, and that deserves a reward.

"I knew it still displeased you, that was why I first chose it to service Fido, but until then, not why, nor why you never let me watch." Yeah, no; the idea of Cas even being in the same room, see what it-- "In retrospect," Cas says, making a face, "perhaps simulating infidelity was not my best idea."

"Fuck that, that was awesome," he protests immediately: come the fuck _on_. "Payoff was totally worth it."

Cas smiles faintly. "So decided." He leans closer with a shift of his hips that gets Dean's undivided attention. "I thought to purge it entirely, but that would not give you the satisfaction it owes you for what it's done," he murmurs, lips brushing Dean's. "Nor does it deserve such mercy. Now, what you teach it, it will learn, and then it may begin to render payment on the infinite debt it has incurred for what it has done to you in its defiance of your will."

"Will it?" Dean says distractedly, then forgets what they were talking about when Cas kisses him, following Cas down onto the firm comfort of the couch, pulling back breathlessly to watch Cas stretch out lazily beneath him; he just never gets tired of watching that. But-- "When does Fido go into heat?"

"Within the next three days," Cas answers, hooking a knee over his hip and drawing him down. "Why? She knows to come here. Oh, I almost forgot: Spado, sit. Your Master will be with you shortly."

Despite himself, Dean looks over to see Spado crouching at the edge of the platform, still grinning, eyes wide and focused on them, tongue out and panting gently. "You want me to do it _now_?"

"I watched you teach them all, save this one," Cas answers huskily, and the hot arousal that's always there when he's with Cas flares to uncontrolled heat across every nerve, like all of Hell burns inside him. "You brought them here and I would watch you take them apart, feeling the pleasure you took in every slice of your knife upon their bodies, in each piece of flesh you carved from their bones, in every scream you drew from them, and knowing that all you did was for me. I would taste their flesh and blood on your skin, proof that you wanted me and me alone, and I felt your pleasure when you moved inside me, knowing you had no rivals and never could, that I wanted only you. It's pain and your pleasure in it you denied me and yourself as well; we will have it from it now. And so will Spado." He meets Dean's eyes and smiles. "Discipline is not always punishment, and so it follows that punishment need not be limited to mere pain. Now it will know all of my pleasure comes from you alone, and to please me, so must its own pleasure, too."

Dean stills as Cas reach down and pull the knife from between them, touching his tongue to the base before trailing it up to the tip.

"What you show it now will be all it can imagine, every time it thinks of me," Cas murmurs. "I promise you, it will eagerly learn whatever you wish to teach. And it will never, ever forget."

"I love you," Dean breathes, leaning down for another hard kiss, unable to pull away before tasting blood, then takes the knife and sits up to look at Spado. "Revert it."

Lazily, Cas raises a hand and snaps his fingers, and Spado drops onto its ass, shaking itself before it sees Dean watching. It's eyes widen, and this time, that hint of defiance inside the terror doesn't bother him at all; instead, he waits, watching it grow. He wants all it can summon this time, it'll just make it better when he slowly starts to take it apart, along with each and every fucking lie.

"Three days," he murmurs, watching it force itself upright. It even tries to stands up, which makes Dean smile; this is gonna be amazing, he can already tell. "I'll barely be getting started."

"Delay will only make Fido more eager," Cas answers, rolling onto his side in a sensual stretch and resting his head on one hand, and way more interesting than anything else in the room right now or pretty much ever. "You are the Master of the Pit and your will is the only law. For your pleasure, all else will wait."

"Then it can wait, too," Dean decides, twisting around to stretch out over Cas and taste his surprised smile. "I got something way more important to do."


End file.
